# Can we harness energy from heliopause?

This question pops up in my mind when I read Bob516's question, indeed even a nuclear reactor can't last forever and anything strayed too far out would not be able to receive significant energy from the Sun.

How about the boundary that separates matters originate from our Sun and the rest of the universe?

Sensors on Voyager 2 confirmed a sharp change in the magnetic field indicating fluctuation in amount of ions while crossing the heliopause so I am wondering if using today's technology are we be able to siphon useful energy from the edge of Solar system or the particle density in that region is so weak that we only use them as "landmark"?

Maybe a 100 years from now could we have the means and capability to mine heliopause otherwise I fear that future of manned space exploration is not going to be promising.

## 2 Answers

What are we talking about when we talk about the flow of particles at the heliopause?

Let's give a look at the data from Voyager-1

As seen from the chart, we drop by an order of magnitude, from about 26 to 2 particles per second for particles having an energy greater than 0.5 MeV.

Since 1 MeV corresponds to $$1.6 \cdot 10^{-13}$$ Joules, we are talking about an available power of about $$10^{-13}$$ W on the surface of the sensor, thus a really miserable amount of energy.

And it makes sense, else the average temperature in that region would be higher than few K.

The heliopause is defined as the point, where the pressure of the solar winds and of the interstellar medium cancel each other out. Just by definition at this point there can't be a high level of energy we could harness in any way. Directly use the energy of our sun like the idea of dyson spheres suggest would be more effective by far.